Abstract
Trade of commodities can lead to virtual water flows between trading partners. When commodities flow from regions of high water productivity to regions of low water productivity, the trade has the potential to generate water saving. However, this accounting of water saving does not account for the water scarcity status in different regions. It could be that the water saving generated from this trade occurs at the expense of the intensified water scarcity in the exporting region, and exerts limited effect on water stress alleviation in importing regions. In this paper, we propose an approach to measure the scarce water saving associated with virtual water trade (measuring in water withdrawal/use). The scarce water is quantified by multiplying the water use in production with the water stress index (WSI). We assessed the scarce water saving/loss through interprovincial trade within China using a multi-region input-output table from 2010. The results show that interprovincial trade resulted in 14.2 km3 of water loss without considering water stress, but only 0.4 km3 scarce water loss using the scarce water concept. Among the 435 total connections of virtual water flows, 254 connections contributed to 20.2 km3 of scarce water saving. Most of these connections are virtual water flows from provinces with lower WSI to that with higher WSI. Conversely, 175 connections contributed to 20.6 km3 of scarce water loss. The virtual water flow connections between Xinjiang and other provinces stood out as the biggest contributors, accounting for 66% of total scarce water loss. The results show the importance of assessing water savings generated from trade with consideration of both water scarcity status and water productivity across regions. Identifying key connections of scarce water saving is useful in guiding interregional economic restructuring towards water stress alleviation, a major goal of China’s sustainable development strategy.
Highlights
A significant amount of the world’s water consumption arises as a result of economic production for trade (Vorosmarty et al 2015)
We propose an approach to measure scarce water savings associated with virtual water trade by considering both the water stress difference and water productivity difference between trading partners
Since scarce water savings suggest the water stress situation between the trading partners as a whole is improved, we argue that the relationship between water saving/loss and alleviation/intensification of regional water stress will produce a useful evaluation and guide for regional water stress alleviation
Summary
A significant amount of the world’s water consumption arises as a result of economic production for trade (Vorosmarty et al 2015). Previous studies have shown water savings are achieved in the trade of commodities at global level (Chapagain et al 2006, Yang et al 2006, Fader et al 2011), and such savings have substantially increased in recent decades alongside increasing volumes of trade (Dalin et al 2012, Konar et al 2012, Konar et al 2013). Efforts towards water saving might be at the expense of intensified water stress in exporting regions, and may exert limited effect on water stress alleviation in importing regions. This situation could happen when the exporting regions are in extreme water stress and the importing regions have minor water stress
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have